According to the United States Center for Disease Control's (CDC) most recent data of 2016, approximately two-thirds of all adults in the United States are considered overweight with a Body Mass Index (BMI) value of over 25. Perhaps even more concerning is that approximately 38% of adults the United States are obese, having a BMI value over 30. (See, Flegal et al., J. of the American Med. Assoc., 315(21):2284-2291, 2016; and Jensen et al., Obesity, 22(S2):S1-S410, 2014). Obese adults have a dramatically higher risk and incidence of metabolic and cardiovascular diseases (CVD). Current weight loss guidelines from organizations such as the American Heart Association, American College of Cardiology, and The Obesity Society, recommend approaches that typically produce modest weight loss, e.g., 5% to 10% of body weight over a 6-month period. (See, “NHLBI: Clinical guidelines on the identification, evaluation, and treatment of overweight and obesity in adults: The evidence report,” Obesity Res., 6:51S-209S, 1998; and US Food and Drug Administration, “Guidance for industry developing products for weight management,” Washington, D.C.: Food and Drug Administration, 2007).
Weight loss guidelines for overweight adults often suggest a combination approach of dietary modification including calorie reduction along with exercise, and/or pharmacological intervention (See, Isoldi et al., Endotext, In: De Groot et al., editors, South Dartmouth (MA), MDText.com, Inc., 2000, ncbi.nlm.nih.gov/books/NBK279038/). A mere 5% change in body weight has been deemed the threshold to meet as a primary efficacy endpoint for a drug/regimen to be considered by the US Food and Drug Administration (FDA). (See, Id.). While some current interventions are modestly effective, many artisans in the field would argue that a loss of 5% of overall body weight, e.g., 12.5 pounds lost with a starting weight of 250 pounds, or severely obese adult, e.g. a weight loss of 17.5 pounds with a starting weight of 350 pounds, is not sufficient to significantly impact a person's health and risk of disease in the long-term.
While reduction of body weight is important, body weight alone is not an adequate measure of reduction in disease risk and improvement in overall health. (See, DesPres et al., Arteriosclerosis, 10:497-511, 1990). There remains a significant need for effective interventions that address more than just the single factor of body weight. Truly meaningful interventions need not to be complicated, can be adopted by a wide range of individuals with different comorbid and health histories, and above all are able to positively affect metabolic and cardiovascular disease risk as measured by endpoints, or surrogates, beyond just body weight.
Many previous studies evaluating dietary interventions fall into two main categories: low calorie diet of less than 850 calories per day alone, or the 850 calorie or less diet combined with various other requirements such as an imposed exercise regimen, pharmacological treatment, and/or surgery. Other prior published studies include diets of more than 850 calories but also optionally include specific exercise regimens and/or pharmacological intervention. For example, the scientific literature includes many examples of calorie-restricted diets, low calorie diets, and very low-calorie diets (VLCDs). (See, for example, Gomez-Arbelaez et al., J. Clin. Endocrinol. Metab., 102(2):488-498, 2017; Claessens et al., Int'l. J. Obesity, 33:296-304, 2009; Gu et al., Evidence-Based Compl. Alt. Med., vol. 2013, Article ID 760804, 2013, doi:10.1155/2013/760804; Hemminsson et al., Am. J. Clin. Nutr., 96:953-961, 2012; Hookey et al., Diabesity in Pract., 3:70-77, 2014; Rolland et al., Clin. Obesity, 3(5):150-158, 2013; Snel et al., Obesity, 20(8):1572-1576, 2012; and Volek at al., Nutrition & Metabolism (Lond.), 1:13, 2004, doi:10.1186/1743-7075-1-13).
However, conventional programs typically fall short of achieving desired goals for one or more reasons. For example, conventional programs do not account for or address the hazards associated with consumption of prepackaged or pre-prepared food items. Conventional diet regimens also typically include lengthy exclusion criteria, including many comorbidities commonly associated with obesity, or include an exercise requirement. Another type of conventional program merely provides a short duration regimen intended to precede bariatric surgery. (See, Cleveland et al., Am. J. Surg., 212(5):927-930, 2016; and Wu et al., Medicine, 95:e2616, 2016). Others require inconvenient and costly in-patient hospitalization (DePergola et al., Obesity Res., 6(6):408-415, 1998), pharmacologic intervention as an adjunct treatment (Doucet et al., Eur. J. Clin. Nutr., 56(4):297-304, 2002; Kelley et al., Diabetes Care, 27:33-40, 2004), and/or inconvenient and difficult to enforce group meeting requirements (Hookey et al., Diabesity in Pract., 3:70-77, 2014; and Rolland et al., Clin. Obesity, 3(5):150-158, 2013).
Most conventional weight loss programs employ an endpoint of weight reduction or change in BMI. These programs experience only modest success. A new approach is needed to combat the epidemic of obesity in the United States. The new approach provided herein employs functional measures or surrogates of cardiovascular and metabolic disease risk instead of simple weight loss end points. In the disclosed methods and compositions, caloric restriction is employed in a very specific manner that yields a reduction in the level and accumulation of visceral adipose tissue (visceral fat). Visceral fat (VF) is a well-characterized direct marker of cardiovascular and metabolic disease risk in both young and old humans. (See, DesPres et al., Circulation, 126:1301-1313, 2012; Goran et al., Am. J. Clin. Nutr., 70S:149S-156S, 1999; and Wade, Marcia, “The Risks of Belly Fat and How to Beat Them,” accessed from webmd.com/obesity/features/the-risks-of-belly-fat#1, 2015). The methods and compositions provided herein are directed to interventions that are motivated by a different goal, i.e. the primary outcome measure is a reduction in VF, which is directly linked to cardiovascular and metabolic disease risk. Unlike conventional weight loss programs, by employing this measure as an end point, astonishing results are obtained in which not only is weight reduced, but subjects experience a marked reduction in risk for cardiovascular and metabolic disease.
What is needed is a generally applicable method of reducing VF in the general population to increase the quality of life and provide clinically significant reductions in the risk of diseases associated with VF. To this end, the disclosed methods and compositions herein are aimed at decreasing this risk factor that is directly linked to cardiovascular and metabolic diseases. The methods disclosed herein employ not simply a reduced calorie diet, but also imposes specific restrictions on the portion size of food categories than can be consumed on a daily basis, as well as the compositions of any consumed foods. These parameters, including duration, calorie level, and/or food portion selection, are fully adjustable to take into account subject-specific variables, such as age, gender, baseline characteristics, relative level of physical activity, or to include adjunctive items to support and sustain safe VF reduction.